fine-grained glassy olivine-free clinopyroxene andesite. Sample is from the center of an isolated pillow within a thick deposit of monolithologic hyaloclastite and interbedded broken pillow breccia layers and autointrusive flow tongues. Whole rock K-Ar date of 1.63 +/- 0.05 m.y. Sample is from pre-Tanada lava, in Tanada area.
Shield volcanoes in the Wrangell Mountains, Alaska